Association between objective and subjective measurements of comfort and discomfort in hand tools

• Published in: Applied ergonomics Vol. 38; no. 5; pp. 643 - 654
• Main Authors: Kuijt-Evers, L.F.M., Bosch, T., Huysmans, M.A., de Looze, M.P., Vink, P.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-09-2007; Elsevier; Elsevier Science Ltd
• Subjects: Adult; Applied physiology; Biological and medical sciences; Comfort/discomfort; Consumer Behavior; Equipment Design; Ergonomics; Ergonomics. Work place. Occupational physiology; Hand - physiology; Hand Strength - physiology; Hand tools; Hands; Human physiology applied to population studies and life conditions. Human ecophysiology; Humans; Male; Measurement; Medical sciences; Middle Aged; Netherlands - epidemiology; Objective measurements; Occupational Health; Pain - epidemiology; Posture; Surveys and Questionnaires; Task Performance and Analysis; Comfort/discomfort; Hand tools; Objective measurements; Human; Manual task; Ergonomics; Objective analysis; Comfort; Saw; Hand; Subjective evaluation; Tool
• ISSN: 0003-6870; 1872-9126
• DOI: 10.1016/j.apergo.2006.05.004

In the current study, the relationship between objective measurements and subjective experienced comfort and discomfort in using handsaws was examined. Twelve carpenters evaluated five different handsaws. Objective measures of contact pressure (average pressure, pressure area and pressure–time (
P–
t) integral) in static and dynamic conditions, muscle activity (electromyography) of five muscles of the upper extremity, and productivity were obtained during a sawing task. Subjective comfort and discomfort were assessed using the comfort questionnaire for hand tools and a scale for local perceived discomfort (LPD). We did not find any relationship between muscle activity and comfort or discomfort. The
P–
t integral during the static measurement (beta=−0.24,
p<0.01) was the best predictor of comfort and the pressure area during static measurement was the best predictor of LPD (beta=0.45,
p<0.01). Additionally, productivity was highly correlated to comfort (beta=0.31,
p<0.01) and discomfort (beta=−0.49,
p<0.01).